diff --git a/configure.in b/configure.in
index cb607c506..80c12dbdf 100644
--- a/configure.in
+++ b/configure.in
@@ -307,6 +307,7 @@ AC_TYPE_UID_T
 SUDO_TYPE_SIZE_T
 SUDO_TYPE_SSIZE_T
 SUDO_FULL_VOID
+SUDO_UID_T_LEN
 SUDO_SOCK_SA_LEN
 dnl
 dnl only set RETSIGTYPE if it is not set already